What is the engine of our body machine презентация

Heart and Blood Vessels

The Human circulatory system
HEART
BLOOD VESSELS

HEART
Is a muscular organ
Consist 4 chambers
two ventricles
two atria
Valves divide ventricle and atria
Valves pretend blood going back
Blood from atria moves to ventricles
Ventricles pump blood out to organs

VESSELS
Three main type blood vessel:
Coming from the heart are called ARTERIAS
That come to the heart are called VEINS
The small network CAPILLARIES connect arterias and veins

ARTERIES
Have dense, smooth and elastic walls
Structure of walls allows the arteries to withstand a great deal of pressure
CAPILLARIES
Exchange of gases and substances between the blood and tissue takes place
Walls are very thin
It helps to oxygen and nutrients enter to tissue
Wastes go out of the tissues
VEINS
Flow to the heart
Walls are thinner than arteries
Blood pressure in them small
Contain valves, which prevent blood in opposite direction

Earthworm Circulatory system
Does not have a heart
Has small body vessels
Vessels pump the blood through the body
Two main blood vessels: Dorsal and Ventral

Mollusks circulatory system
Have a Heart
Consist of one Ventricle and one or two Atria
Vessels pour blood into body
Blood interacts with organs and tissues
Collects to vessels again